• 4 studies• Decreased Breast Cancer Risk:o Significantly associated with activity during adolescence, high levels of activity before age 30, and lower levels of activity after age 30 in BRCA1/2b(Lammert, 2018; Pijpe, 2010)• No association for activity two years before diagnosis and breast cancer risk in BRCA1/2b(Nkondjock,Robidoux, 2006)• For Ashkenazi Jewish women, engagement in physical activity as teenager associated with delayed onset breast cancer(King, 2003)

fOne study observed no association(Gronwald, 2006) and one study observed OR0.51(0.26,0.98) for total coffee consumption in relation to breast cancer risk(Nkondjock, Ghadirian, 2006)

gThree studies observed no association between alcohol intake and breast cancer risk in BRCA1/2 variants collectively(Cybulski, 2015; Nkondjock, Robidoux, 2006; Lecarpentier 2011), one study observed an association in BRCA1 but not BRCA2 when tobacco use was included as an interaction(Lecarpentier, 2011), one study observed an association in BRCA1 but not BRCA2(Dennis, 2010), one study observed a weak effect of alcohol when comparing breast cancer survivors compared to survivors without BRCA, no effect was observed for BRCA2(Moorman, 2010), one study observed an association in BRCA2 but not BRCA1(McGuire, 2006), one study observed an effect for alcohol when comparing survivors with BRCA2 to survivors without BRCA, but an effect was not observed in BRCA1(Dennis, 2011)

hOne study(King, 2003) assessed weight status and physical activity

iAssociation applies to pre- and post-menopausal breast cancer risk

jOne study observed a significant association with weight gain since age 18 and 30 and increased breast cancer risk for BRCA1/2 variants (Nkondjock, Robidoux 2006), one study did not observe a significant association with 10–20 or > 20 lb. weight gain between the ages of 18 and 30 for BRCA1/2 variants collectively and by variant, and when age at diagnosis was between 30 and 40 years or > 40 years (Kotsopoulos, 2005)